<?php
/**
 * Add links to nodes to allow simple toggling between read/write and read-only comments - known as freeze / un-freeze
 */

/**
 * Implementation of hook_menu()
 */
function freeze_node_menu($may_cache){
  $items = array();

  if (!$may_cache){
    $items[] = array(
      'path' => 'freeze-node',
      'type' => MENU_CALLBACK,
      'access' => TRUE,
      'callback' => 'freeze_node_callback'
    );
    $items[] = array(
      'path' => 'admin/settings/node-freeze',
      'type' => MENU_NORMAL_ITEM,
      'access' => user_access('administer site configuration'),
      'description'=>t('Manage the node freeze module'),
      'title' => t('Node freeze'),
      'callback' => 'drupal_get_form',
      'callback arguments' => array('freeze_node_settings')
    );    
  }
  
  return $items;
}


/**
 * A basic settings form
 */
function freeze_node_settings(){
  $form['node_freeze_remove_label']=array(
    '#title'=>t('Label for un-freezing node'),
    '#type'=>'textfield',
    '#default_value' => variable_get('node_freeze_remove_label',t('Un-freeze'))
  );
  
  $form['node_freeze_add_label']=array(
    '#title'=>t('Label for freezing node'),
    '#type'=>'textfield',
    '#default_value' => variable_get('node_freeze_add_label',t('Freeze'))
  );
  
  return system_settings_form($form);
}


/**
 * Handle the menu callback, either freeze or unfreeze the node 
 */
function freeze_node_callback($nid=0,$action='toggle',$silent=false){
  
  if ($nid){
    $node = node_load($nid);
    if (node_access('update', $node) && user_access('can freeze nodes they can edit')){
      
      $origional_state = $node->comment;
      
      if ($action=='toggle'){
        if ($node->comment == COMMENT_NODE_READ_ONLY){
          $action = 'thaw';
        }
        if ($node->comment == COMMENT_NODE_READ_WRITE){
          $action = 'freeze';
        }        
      }
      
      switch($action){
        case 'thaw' : 
          $node->comment = COMMENT_NODE_READ_WRITE;
          break;
        case 'freeze' : 
          $node->comment = COMMENT_NODE_READ_ONLY;
          break; 
        case 'disable' :         
          $node->comment = COMMENT_NODE_DISABLED;
          break;
      }
      
      if ($node->comment != $origional_state){
        node_save($node);
        if (!$silent){
          drupal_set_message(t('Reply settings have been updated'));
          drupal_goto('node/'.$nid);
        }
      }
    }
  }
}


/**
 * Add freeze / unfreeze links to the node as requried.
 */
function freeze_node_link($type, $node = NULL, $teaser = FALSE){
  $links = array();
  
  //show these links for any node that has commenting enabled.
  if ($type=='node' && $node->comment){
    if (node_access('update', $node) && user_access('can freeze nodes they can edit')){
      if ($node->comment == COMMENT_NODE_READ_ONLY){
        $label = variable_get('node_freeze_remove_label',t('Un-freeze'));
        $link_key = 'un-freeze';
      }
      else {
        $label = variable_get('node_freeze_add_label',t('Freeze'));
        $link_key = 'freeze';
      }
      $links[$link_key] = array(
          'title' => $label,
          'href' => "freeze-node/$node->nid",          
      );
    }
  }
  return $links;
}


/**
 * Define a set of operations so you can do this stuff en-mass on the admin/content/node form
 */
function freeze_node_node_operations() {
  $operations = array(
    'freeze_hide' => array(
      'label' => t('Freeze and hide comments'),
      'callback' => 'freeze_node_operations_callback_remove',
    ),  
    'freeze' => array(
      'label' => t('Freeze comments'),
      'callback' => 'freeze_node_operations_callback_freeze',
    ),
    'unfreeze' => array(
      'label' => t('Unfreeze (enable) comments'),
      'callback' => 'freeze_node_operations_callback_unfreeze',
    ),
    
  );
  return $operations;
}


/**
 * Disable comments completely on each node in turn
 */
function freeze_node_operations_callback_remove($nids){
  foreach ($nids as $nid) {
    freeze_node_callback($nid,'disable',TRUE);        
  }
}


/**
 * Freeze each node in turn
 */
function freeze_node_operations_callback_freeze($nids){
  foreach ($nids as $nid) {
    freeze_node_callback($nid,'freeze',TRUE);        
  }
}


/**
 * Thaw each node in turn
 */
function freeze_node_operations_callback_unfreeze($nids){
  foreach ($nids as $nid) {
    freeze_node_callback($nid,'thaw',TRUE);        
  }
}